Typically, feed systems for feeding sheet-like materials, such as paperboard, or paper or plastic sheets and the like, comprise at least one feed roller or one or more idler rollers in combination therewith. For example, the feed roller may comprise a driven hard roller on the bottom, such as a steel roller having a knurled surface, or a hard elastomeric surface roller with an idler roller positioned above the feed roller. Where the feed system is to feed sheet materials, for example, of various thickness, adjustments can be made to the feed or idler roller to provide for different thicknesses. Often such feed material requires an energy source to adjust the tension or surface pressure on the material to be fed when the material changes in thickness or dimension. Such adjustment of surface pressure or tension is accomplished by mechanical, electrical or hydraulic systems, or by merely removing and respacing the distance between the feed and idler rollers to obtain the desired surface pressure for feeding purposes. Such systems require constant adjustment as material of different dimensions are fed through the system or require complex systems to adjust the tension or surface pressure.
A self-adjusting roller, either as a feed roller or an idler roller, would be desirable where such a roller would conform to various thicknesses of materials being used in the system; that is, being rolled over or under without any outside energy sources for adjusting or moving the roller.
Resilient-type rollers have been developed for various purposes. For example, U.S. Pat. No. 2,572,276 discloses a resilient roller prepared from an extrudable material, the roller having a corrugated surface and having a central opening through the shaft and surrounded by a plurality of pear-shaped openings. Resilient rollers have also been employed in handling fragile-type materials, such as eggs, as shown in U.S. Pat. No. 3,272,309, wherein a transport member comprises a core portion and has a plurality of generally circular openings about the outer portion of the roller. The roller is formed of resilient material and has circular openings of such dimensions that the eggs to be transported may be moved under the roller without damage.